Isometric (static) exercise differs from isotonic (dynamic) exercise in that
it causes a greater increase in
A. Venous return.
B. Pressure in the veins draining the exercising muscle.
C. Muscle blood flow.
D. Mean arterial pressure.
E. Cardiac work for the same increase in cardiac output.
The correct answer is D. Mean arterial pressure. Isometric exercise causes a greater increase in mean arterial pressure due to sustained muscle contraction, which compresses blood vessels and raises vascular resistance.
Pressure in veins draining the exercise muscle
Explanation – The muscle pump increases venous return during dynamic exercise, lowering venous pressure in dependent veins. Cardiac output must be ejected against a higher aortic pressure, a rise in arterial pressure with static exercise increases cardiac work.